1. Field of the Invention
The present invention relates to an input device for operational instructions which is incorporated in a facsimile machine, a facsimile machine with a copying function or the like, and more particularly to an operational input device characterized by the way how the operational instructions are input.
2. Description of the Related Art
For example, a facsimile machine with a copying function has many keys in an operation unit in order to instruct details of copying operation, and facsimile operation. More particularly, the operation unit has a fax/copy key to set the machine in a fax mode or a copy mode, a numerical key pad to input fax numbers of the receiving party or the number of copy sheets, a one-touch dial key to set (dial) receiving party's fax numbers, and a start key that starts the scanning of documents. In addition, there are keys used to set applied communication such as broadcasting. Using these keys in an appropriate order can execute desired type of facsimile communication and copying.
However, because these keys are independent and gathered in the operation unit, there has been a limit to miniaturization. Therefore, a system with reduced number of keys has been known where the operational keys with similar functions and not used so often are gathered and arranged in a layered system. However, there has still been a limit for miniaturization even if the keys are arranged in a layered system.